A convergent totalsynthesis of achaetolide is described. The key steps include a Horner-Wadsworth-Emmons olefination, CBS reduction to install the stereochemistry at the C9 center, stereoselective vinylation to introduce the chiral center at C6, and finally a ring-closing metathesis (RCM) reaction to construct the ten-memberedlactone of the molecule. macrocycles - metathesis - stereoselective synthesis